Hope you have got to the bottom of it, thought you were confident that it was a "mechanical" stop* and had ruled it out anything else. If stalling naturally as opposed to * then cigar goes to @WAH900ss for re-introducing the idea.
There might be a bit of wishful thinking going on here, but I will certainly report back… I think dropping the oil and pulling off the the engine casing has given me a little more confidence. We’ll see….
